Abstract

Highly hexagonally ordered hard anodic aluminum oxide membranes, which have been modified
by a thin cover layer of SiO2 deposited by atomic layer deposition method, were used as templates for the synthesis
of electrodeposited magnetic Co-Ni nanowire arrays having diameters of around 180
to 200 nm and made of tens of segments with alternating compositions of Co54Ni46 and Co85Ni15. Each Co-Ni single segment has a mean length of around 290 nm for the Co54Ni46 alloy, whereas the length of the Co85Ni15 segments was around 430 nm. The composition and crystalline structure of each Co-Ni
nanowire segment were determined by transmission electron microscopy and selected
area electron diffraction techniques. The employed single-bath electrochemical nanowire
growth method allows for tuning both the composition and crystalline structure of
each individual Co-Ni segment. The room temperature magnetic behavior of the multisegmented
Co-Ni nanowire arrays is also studied and correlated with their structural and morphological
properties.